• 제목/요약/키워드: Research method

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Response spectrum analysis considering non-classical damping in the base-isolated benchmark building

  • Chen, Huating;Tan, Ping;Ma, Haitao;Zhou, Fulin
    • Structural Engineering and Mechanics
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    • 제64권4호
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    • pp.473-485
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    • 2017
  • An isolated building, composed of superstructure and isolation system which have very different damping properties, is typically non-classical damping system. This results in inapplicability of traditional response spectrum method for isolated buildings. A multidimensional response spectrum method based on complex mode superposition is herein introduced, which properly takes into account the non-classical damping feature in the structure and a new method is developed to estimate velocity spectra from the commonly used displacement or pseudo-acceleration spectra based on random vibration theory. The error of forced decoupling method, an approximated approach, is discussed in the viewpoint of energy transfer. From the base-isolated benchmark model, as a numerical example, application of the procedure is illustrated companying with comparison study of time-history method, forced decoupling method and the proposed method. The results show that the proposed method is valid, while forced decoupling approach can't reflect the characteristics of isolated buildings and may lead to insecurity of structures.

인삼사포닌 화합물의 신속한 추출 (An Rapid Extraction of Ginseng Saponin Compounds)

  • 곽이성;김미주;김은희;김영애
    • 한국식품과학회지
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    • 제29권6호
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    • pp.1327-1329
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    • 1997
  • 인삼으로부터 사포닌 화합물의 신속한 추출방법을 모색하기 위하여 waring blonder 와 유기용매를 이용한 새로운 추출방법을 개발하였다. 본 방법은 기존의 인삼 증류추출방법과 비교해볼 때 6개의 주종 사포닌($ginsenoside-Rb_2$, $ginsenoside-Rb_1$, ginsenoside-Rc, ginsenoside-Rd, ginsenoside-Re, $ginsenoside-Rg_1$) 함량이 유사하여 유의성이 있는 것으로 생각된다. 유기용매는 메탄올과 클로로포름을 7:3의 비율로 사용하였을 때 사포닌 화합물이 잘 추출되었다. 5개의 주종사포닌을 합한 전체 사포닌 함량은 본 방법에서는 2.41% 이었고 기존의 방법 에서는 2.54%이었다. 그러나 조사포닌의 함량은 본 방법이 기존의 방법보다 높은 것으로 나타났다.

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수중 방사능 측정시 이온교환농축법과 증발건조법의 비교 (Comparison of the Ion-exchange Method and Evaporation Method for the Detection of Radioactivity in Water)

  • 지평국;박종묵;노성기
    • Journal of Radiation Protection and Research
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    • 제13권2호
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    • pp.52-56
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    • 1988
  • 수중의 방사능을 측정하기 위한 전처리과정으로서 이온교환농축법과 증발건조법을 서로 비교하였다. 시료를 증발건조법으로 처리하였을때 방사성물질의 손실율은 이온교환농축법에 비해 20% 정도 많았다. 또, 1리터의 시료를 처리하는 데 소요된 증발시간은 $70^{\circ}C$에서 증발시킨 경우 약20시간이었으나 이온교환농축법으로 같은 양의 시료를 처리하는데 소요된 시간은 약6시간이었다. 따라서 이온교환농축법이 증발건조법에 비해 효과적이며 특히 수중의 저준위 방사성물질 측정에 적합한 것으로 나타났다.

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전위상승에 대한 독립접지방식과 공통접지방식의 비교 (Comparison of Individual and Common Grounding Method for Potential Rise)

  • 길형준;김동욱;김동우;이기연;최충석
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 춘계학술대회 논문집 전기설비전문위원
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    • pp.41-43
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    • 2006
  • This paper deals with a comparison of individual and common grounding method for potential rise. When a test current flowed through grounding electrode, potential rise was measured and analyzed for grounding method using a electrolytic tank in real time. The grounding electrodes were designed and fabricated with ground rods on a scale of one-eightieth. Potential rises of individual grounding method were higher than those of common grounding method. The distributions of surface potential are dependent on the distance from grounding electrode.

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The TROPHY (Talented Role-playing Technology with a Dual Polarity Sustainer in Hybrid Mono Board) Driving Method

  • Park, Chang-Joon;Kwak, Jong-Woon;Kim, Tae-Hyung;Park, Hyun-Il;Moon, Seong-Hak
    • Journal of Information Display
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    • 제7권4호
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    • pp.24-26
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    • 2006
  • We have developed a new driving method named TROPHY(Talented Role-playing Technology with Dual Polarity sustainer in Hybrid Mono board). In this method, the sustain voltage is partially compared to the conventional method and the number of power sources is reduced by voltage level unification during the reset, address and sustain period. The hybrid mono board was especially developed to implement those technologies. Through this, we can lower the cost with the TROPHY compared to the conventional one. It is a suitable technology to improve the reliability of circuit and image sticking problem. We can also reduce the number of driving boards and the EMI problem compared with those of the conventional method.

The TROPHY (Talented Role-playing Technology with a Dual Polarity Sustainer in Hybrid Mono Board) Driving Method

  • Park, Chang-Joon;Kwak, Jong-Woon;Kim, Tae-Hyung;Park, Hyun-Il;Moon, Seong-Hak
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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    • pp.246-249
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    • 2006
  • We have developed a new driving method named TROPHY(Talented Role-playing Technology with Dual Polarity sustainer in Hybrid Mono board). In this method, the sustain voltage is halved compared to the conventional method and the number of power sources is reduced by voltage level unification during the reset, address and sustain period. The hybrid mono board was especially developed to implement those technologies. Therefore, we can lower the cost with the TROPHY compared to the conventional one. It is suitable technology to improve the reliability of circuit and image sticking problem. We can also reduce the number of driving boards and the EMI problem comparing to those of the conventional method.

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Identification of reinforced concrete beam-like structures subjected to distributed damage from experimental static measurements

  • Lakshmanan, N.;Raghuprasad, B.K.;Muthumani, K.;Gopalakrishnan, N.;Basu, D.
    • Computers and Concrete
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    • 제5권1호
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    • pp.37-60
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    • 2008
  • Structural health monitoring of existing infrastructure is currently an important field of research, where elaborate experimental programs and advanced analytical methods are used in identifying the current state of health of critical and important structures. The paper outlines two methods of system identification of beam-like reinforced concrete structures representing bridges, through static measurements, in a distributed damage scenario. The first one is similar to the stiffness method, re-cast and the second one to flexibility method. A least square error (LSE) based solution method is used for the estimation of flexural rigidities and damages of simply supported, cantilever and propped cantilever beam from the measured deformation values. The performance of both methods in the presence of measurement errors is demonstrated. An experiment on an un-symmetrically damaged simply supported reinforced concrete beam is used to validate the developed method. A method for damage prognosis is demonstrated using a generalized, indeterminate, propped cantilever beam.

A new contrast ratio measurement method using image patterns

  • Choi, Dong-Wook;Yang, Sun-A;Bae, Jae-Woo;Lee, Seung-Bae;Chung, Ho-Kyoon
    • Journal of Information Display
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    • 제12권2호
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    • pp.85-87
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    • 2011
  • The contrast ratio is one of the most important performance parameters for display devices. The general method of measuring the contrast ratio is to determine the ratio of the full-screen white pattern to the full-screen black pattern, according to the Video Electronics Standards Association standard. Real TV images seldom have these images, however, and the conventional method does not reflect the true performance of the display in actual use. In this paper, a new contrast ratio measurement method that uses image patterns is proposed, to demonstrate that active matrix organic light-emitting diode TVs have a higher contrast than LED (LCD) TVs.

The Boundary Element Analysis of Wave Force acting on Multiple Cylinders

  • Kim, Nam-Hyeong;Cao, Tan Ngooc Than;Yang, Soon-Bo
    • 한국항해항만학회지
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    • 제36권7호
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    • pp.561-569
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    • 2012
  • In this paper, the boundary element method is applied to solve the diffraction of waves by multiple vertical cylinders under the assumption of linear wave theory. A numerical analysis by boundary element method is based on Green's theorem and introduced to an integral equation for the fluid velocity potential around the cylinders. The numerical results obtained in this study are compared with the experimental data and the results of the theory using multiple scattering techniques. The comparisons show strong agreement. This numerical analysis method developed by using boundary element method could be used broadly for the design of various offshore structures to be constructed in coastal zones in the future.

iHaplor: A Hybrid Method for Haplotype Reconstruction

  • Jung, Ho-Youl;Heo, Jee-Yeon;Cho, Hye-Yeung;Ryu, Gil-Mi;Lee, Ju-Young;Koh, In-Song;Kimm, Ku-Chan;Oh, Berm-Seok
    • 한국생물정보학회:학술대회논문집
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    • 한국생물정보시스템생물학회 2003년도 제2차 연례학술대회 발표논문집
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    • pp.221-228
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    • 2003
  • This paper presents a novel method that can identify the individual's haplotype from the given genotypes. Because of the limitation of the conventional single-locus analysis, haplotypes have gained increasing attention in the mapping of complex-disease genes. Conventionally there are two approaches which resolve the individual's haplotypes. One is the molecular haplotypings which have many potential limitations in cost and convenience. The other is the in-silico haplotypings which phase the haplotypes from the diploid genotyped populations, and are cost effective and high-throughput method. In-silico haplotyping is divided into two sub-categories - statistical and computational method. The former computes the frequencies of the common haplotypes, and then resolves the individual's haplotypes. The latter directly resolves the individual's haplotypes using the perfect phylogeny model first proposed by Dan Gusfield [7]. Our method combines two approaches in order to increase the accuracy and the running time. The individuals' haplotypes are resolved by considering the MLE (Maximum Likelihood Estimation) in the process of computing the frequencies of the common haplotypes.

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